There are various known methods of measuring the inclination of surfaces which include optical measurement tools and complicated measurement tools.
One of the simplest tools for measuring the inclination of a surface is the spirit level (sometimes known as a bubble level). A spirit level device typically includes a longitudinal container which contains a liquid and a “bubble” of a material having a lower density than the surrounding liquid. Due to the relative densities of the bubble and the surrounding liquid, the bubble always tends to rise relative to the liquid, in accordance with Archimedes' principle, to its highest local point relative to the gravitational vertical axis as determined by the confines of the container. Therefore, if there is any inclination in the longitudinal container, the buoyant forces acting on the bubble cause it to rise in the liquid towards its highest gravitational point permitted by the container. Thus, a user will be able to determine whether the surface that the spirit level is resting on or held against has an inclination or not by the behavior of the bubble. The spirit level may include reference lines to assist the user in monitoring the position and any movement of the bubble.
The spirit level is therefore a very simple, yet effective, device for indicating the presence of an inclination. However, a spirit level such as the one described above is incapable of indicating the extent of the inclination beyond the horizontal plane and is therefore of limited use when more detailed and specific information is required.
It is an object of the present invention to provide a measurement device that is capable of indicating that a surface has an inclination and that is additionally capable of providing more specific angle-related information about the extent of the inclination.